1. Field of the Invention
The present invention relates to an atomizer, and more particularly to a miniature atomizer of manual type for atomizing a liquid such as perfume or cosmetic preparations, in a state of fine spray.
2. Description of the Prior Art
A miniature atomizer of the so-called "aerosol" type has been widely used heretofore because of its convenience in handling. Atomizers of this type have, however, certain drawbacks, e.g., its production cost is relatively high and carrier gases are inevitably left in its container even after disposal. The latter drawback becomes serious sometimes since the atomizer confining such combustible gases may be caused to unintentionally explode due to some cause. Accordingly, for these reasons, the attentions of users are again attracted to a miniature atomizer of the manual type disclosed herein which inherently has none of those drawbacks.
In the manual-type miniature atomizer, a coil spring is currently used to return the atomizer head to its original non-actuated position. Elements or parts including such coil spring become similar and smaller as a consequence of scaling-down the miniature atomizer as a whole. Thus, assembly of the smaller atomizers becomes much more difficult, and furthermore these elements from which they are built are liable to be lost. For a miniature atomizer having a complicated construction, therefore, not only its overall assembly is difficult, but also it requires many steps and delicate skills to mount the return coil spring in position.
The present invention is directed to improvements upon an invention disclosed in our U.S. Pat. No. 3,908,870, issued Sept. 30, 1975. The invention of that patent relates to a highly efficient miniature atomizer of manual type, which has a relatively complicated structure. Generally speaking, in order to improve the pumping efficiency of such a complicated miniature atomizer, it is conceivable to provide a member which is operative to reduce the working chamber defined mainly by a sliding tubular member, as used in miniature atomizers. It is, however, difficult to assemble the tubular member into the atomizer without deteriorating efficiency in the overall assembly process.
Another difficulty to be solved in the use of a miniature atomizer including the atomizer disclosed in our earlier patent is that the possibility of leakage of a working liquid is increased since the atomizer is designed in such a manner that the compressed air is allowed to be exhausted to the open air as well as into the inside of the liquid container, when the tubular piston is moved downward to its lowermost position, so that the liquid can be introduced reliably into the pressure chamber by just a short spray priming time even for the first use.